Honda BF 150 Valve Clearance check.

[Schuster]

Good morning C-Brats, I have a question concerning the Honda BF150 motor maintenance. I am doing my annual winterization of basic oil change, rv antifreeze in the fresh water lines, changed lower unit lube, replaced water pump impeller (3 Years use). I also changed out the thermostats and cleaned the ports of salt residue. My question has to do with valve adjustment.... my 150 has over 800 hours on it and is still running flawlessly but according to the maintenance schedule the valve clearance should be checked every year or 200 hours. This is an expensive procedure at $180/hr for shop labor. Honda service shop who suggested that unless it is hard starting or not running properly most people wont bring them in. Has anyone had trouble with valves being out of clearance? Am I over thinking this as the motor runs perfectly? I plan on changing the plugs myself and will do a compression check for reassurance that all is well.

[kaelc]

I don’t believe my mechanic ever does this. Sounds like you are doing the most important maintenance. I’m at 1240 hours on the same engine

[T.R. Bauer]

I would say it's generally not needed. I used to check mine every couple of years, but each time they were nearly spot on. FWIW I have nearly 3000 hours on my Honda outboards. They also recommend changing timing belts way too often as well. I've inspected mine several times, but they always looks fine....not taking off a perfectly good timing belt to put on a different perfectly good timing belt.

[ssobol]

If it ain't broke don't fix it.

I used to check the valve clearance on various car and boat engines I owned according to the maintenance manuals. I never found it to change enough to need adjustment and stopped doing it.

If the valve clearance is a little off you might notice a decrease in performance. If the timing belt lets go or slips enough, your engine is toast.

[Schuster]

Thanks for your input on checking my valve clearances. Youve raised some more questions regarding timing belt replacement. Looking at my repair manual i figured out that i don't have a timing belt but a timing chain is used on the 135 and 150 outboards. I think I'll just have the honda mechanics check that for me if required .. Again, thanks!

[Hunkydory]

On our old Honda 40’s, I checked the valves twice in 2400 hrs. The first time at 800 hours they needed a slight adjustment. The 2nd at about 1600 hours none.

The replacement Honda 60’s now have 540 hours & I will be checking the valves & adjusting if needed with planning on checking them about every 400 hrs in the future. I did considerable research on the necessity of this & found the opinions highly varied. The main take away, it is rare, they actually need adjusting, but if to tight, the likelihood of major engine damage high, so with me wanting these motors to last, I think checking them every 400 hours reasonable. Besides it’s just not that hard to do it on a Honda.

This fall along with the normal racor fuel filters, engine oil & filters & lower unit oil change, I’m doing the complete water pumps, high & low pressure fuel filters, all anodes, valve adjustment, timing belt adjustment & thermostat inspection. I have a shop manual & none of this is very complicated.

I was very pleasantly surprised to see how clean the thermostats & the inner area behind them are after over 500 hours, compared especially to the old Honda 40’s that always had buildup. Also the water pumps looked new, though being as I had the parts, I replaced them all anyway.

Even if where I live wasn’t so isolated & certified Honda marine shops far away, I would still do all this type of work myself as my trust in them doing a good job is not high.

[ssobol]

Adjustment of the valves is to compensate for wear of either the valve seat or the face of the valve where it hits the seat. The idea is to make sure the valves close all the way. If you want to do a quick check just make sure that there is a little clearance (wiggle) of the rocker arm when the associated valve is closed. Make sure the engine is at operating temp before you check this.

[Hunkydory]

[ssobol]

[Hunkydory]